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The cell wall of opportunistic pathogenic yeast fungi Candida and mould fungi Aspergillus is highly important for the pathogenesis of fungal infections, as it is the first to interact with the cells of the host organism, is responsible for pathogen adhesion and intra- and intercellular communications and bears important antigenic determinants. Fungal cell walls are composed mainly of polysaccharides. Methods that are currently used to study biological functions of cell wall polysaccharides require samples that are structurally characterized and have sufficient homogeneity and purity. However, the isolation of such samples from fungal cultures is often poorly feasible. Therefore, synthetic oligosaccharides of strictly specified structure corresponding to polysaccharide fragments of the cell wall of pathogenic fungi are indispensable tools for investigating the biological functions of such compounds. The review surveys studies devoted to the synthesis of oligosaccharides corresponding to fragments of major polysaccharide components of the fungal cell wall of Candida and Aspergillus: mannan, a- and b-(1-3)-glucans, chitin, galactosaminogalactan and galactomannan. The bibliography includes 140 references.

The review addresses the application of synthetic oligosaccharides related to fragments of capsular polysaccharides from different serotypes of the bacterium Streptococcus pneumoniae for the design of third-generation pneumococcal conjugate vaccines. Special focus is given to characteristic features of the chemical structures of oligosaccharides required for the induction of the protective immune response when using synthetic glycoconjugate vaccines based on oligosaccharide ligands and carrier proteins. The bibliography includes 101 references.

Data on the main approaches to preparation of mono- and oligodentate glycoconjugates based on porphyrin scaffolds are surveyed. The prospects for using these compounds as sensitizers for photodynamic therapy of cancer and for suppression of bacterial and viral pathogens are considered. Data on the synthesis of oligodentate blocking agents for carbohydrate-binding proteins (lectins) based on porphyrin scaffolds are discussed. The bibliography includes 161 references.

The applicability of terminated oligomerization to the synthesis of oligo-(β1-6)-glucosamines, fragments of the intercellular polysaccharide adhesin of staphylococci, was studied. The reactions of terminated oligomerization were carried out with mono-, di-, and trisaccharide monomers and N-protected aminopropanol; and spacered mono-and disaccharides as terminating molecules were also attempted. The primary formation of cyclic products of monomer intramolecular glycosylation was observed in almost all the reactions. Only the experiments with the monomer based on the disaccharide bromide under the conditions of the Helferich reaction led to reduced yields (30%) of the cyclic products. However, even in this case, the desired terminated oligosaccharides were generated in approximately 10% yield and mainly were the products of single glycosylation of the terminator by the monomer. These experiments allow the conclusion that, under the examined conditions, the reaction of terminated oligomerization could not result in the synthesis of oligoglucosamines with a high molecular mass.

The driving force for the constant improvement and development of synthetic methodologies in carbohydrate chemistry is the importance of natural oligosaccharide chains in numerous biological phenomena such as cell growth, differentiation, adhesion, etc. Here, we report our syntheses of the spacer-armed oligosaccharides of sialylated lacto- and neo- lacto-, globo-, ganglio-, and sulfoglucuronylparagloboside-series, which include new rationally designed synthetic blocks, efficient solutions for the stereoselective construction of glycosidic bonds, and novel protection group strategies.

Biotinylated glycoconjugates which were designed as oligosaccharides attached to 30 kDa polyacrylamide were coated on a microarray platform XNAonGOLD™, which was developed earlier for an oligonucleotide assay. The specificity of antibodies to carbohydrate antigens was analyzed using the glyco-microarray. Comparison of the obtained results with those of common 96-well plate ELISA completely coincided with the found antibody specificities. However, parameters such as the analytical sensitivity of the method and the amount of biotinylated material coated on the microarray platform proved to be worse than expected.

Sodium-carboxymethylcellulose and arabinogalactane inhibits the crystallization of calcium carbonate from a supersaturated aqueous solution at 80degC. The sizes of formed crystals CaCO3 in the presence of arabinogalactane, sodium-carboxymethylcellulose and neonol AF 9-10 decrease on an average 7-12 um and a change of their structure. It is expected, that the mechanism of inhibitionis in specific adsorption polysaccharides and neonol on occurring crystalline surface of the calcium carbonate, both at the expense of electrostatic interaction of functional groups with Ca2+ ions, located on the surface of the crystal, and due to coordination and hydrogen bonds with oxygen atoms and HO-groups of additives. Oil-water emulsion rheology in the presence of neonol AF 9-10 has been studied. It is shown that neonol AF 9-10 decrease viscosity natural water-oil emulsion by 25 times. Addition of 5% neonol to water-oil emulsion leads to formation more than 20 stable emulsion forms of different density and composition. New highly effective "green" oilfield reagents have been developed on the basis of neonol and natural polysaccharides.

The review addresses the application of synthetic oligosaccharides related to fragments of capsular polysaccharides from different serotypes of the bacterium Streptococcus pneumoniaefor the design of third-generation pneumococcal conjugate vaccines. Special focus is given to characteristic features of the chemical structures of oligosaccharides required for the induction of the protective immune response when using synthetic glycoconjugate vaccines based on oligosaccharide ligands and carrier proteins.

Data on the main approaches to preparation of mono- and oligodentate glycoconjugates based on porphyrin scaffolds are surveyed. The prospects for using these compounds as sensitizers for photodynamic therapy of cancer and for suppression of bacterial and viral pathogens are considered. Data on the synthesis of oligodentate blocking agents for carbohydrate-binding proteins (lectins) based on porphyrin scaffolds are discussed.

Review: 69 refs.

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract, please click on HTML or PDF.

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract, please click on HTML or PDF.

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